The city of Portland is warning residents who typically leave their vehicles on the street overnight on the peninsula that it has posted emergency red and green no-parking signs to allow for snow removal between 11 p.m. and 7 a.m. this week. The city said plow crews need access to both sides of streets, and vehicles could be towed. The temporary parking ban applies to the downtown area and the East End and West End neighborhoods. Snow ban parking is offered on Cutter Street, the Eastern Prom, Western Prom, Deering Oaks, State Street, and at school lots.